The disclosure of the following priority application is herein incorporated by reference:
Japanese Patent Application No. 10-65165 filed Mar. 16, 1998.
1. Field of the Invention
The present invention relates to an electronic still camera and more specifically, it relates to the positional arrangement of electric circuit parts and image display system parts.
2. Description on the Related Art
There are electronic still cameras in the known art that perform photoelectric conversion of photographic light from a subject by employing an imaging element and store the subject image as electronic data. A single lens reflex type electronic still camera is a type of electronic still camera. As in the case with silver halide type cameras, there is a need for achieving miniaturization and improvements in the operability and image quality with respect to such single lens reflex type electronic still cameras. While a single lens reflex type electronic still camera shares certain common aspects with a silver halide type camera, its structure is essentially different since it stores subject images as electronic data. FIG. 5 illustrates an example of single lens reflex type electronic still cameras in the known art. It is to be noted that the left/right direction and the front/rear direction in the figure respectively represent the left/right direction and the front/rear direction with respect to the single lens reflex type electronic still camera.
In the figure, reference number 101 indicates the single lens reflex type electronic still camera which is provided with a casing 102.
An opening is formed on the left side of a front wall 103 of the casing 102. A cylindrical portion is provided, constituting an integrated unit with the opening, and a lens 104 is secured within the cylindrical portion.
An image-capturing element 105 is provided at an approximate center of the casing 102 in the front/rear direction. The image-capturing element 105, which extends perpendicular to a plane M1 that includes the lens optical axis of the lens 104 and the viewfinder optical axis, is positioned to achieve symmetry in the left/right direction.
A grip unit is formed at the right side of the casing 102 in the left/right direction. The grip unit 106 is formed with a bend projecting out a further forward relative to the front wall 103 of the casing 102.
Thus, only the grip unit 106 is provided to the right side relative to the plane Ml that includes the lens optical axis and the viewfinder optical axis. As a result, there is no portion on the left side that corresponds to the grip unit 106 so that the casing 102 forms a rough L shape in the plan view, which is asymmetrical in the left/right direction.
An image-capturing element board 107, a first electric circuit board 108 and a second electric circuit board 109 are positioned sequentially at the rear side of the image-capturing element 105.
On the first electric circuit board 108 and the second electric circuit board 109, an image display drive circuit such as, for instance, an image display circuit and an inverter circuit, and a recording compression circuit are mounted.
At the rear side of the second electric circuit board 109, an illuminating light source 110 is provided at a position that is almost aligned with that of the image-capturing element 105 in the left/right direction, with a liquid crystal display unit 111 provided at the rear side of the illuminating light source 110.
A battery box 112 is provided inside the grip unit 106, with batteries 113 housed inside the battery box 112.
Toward the rear and to the right of the second electric circuit board 109, a connector 114 for an external recording member is provided along the left/right direction.
In the single lens reflex type electronic still camera 101 in the known art, in which the first electric circuit board 108 and the second electric circuit board 109 are provided at the rear side of the image-capturing element 105 next to each other extending in the left/right direction, the entire thickness of the casing 2 is much larger than that in a silver halide type single lens reflex camera. This results in the single lens reflex type electronic still camera 101 becoming bulky and difficult to hand hold, which, in turn, results in a great reduction in operability and poor ergonomics.
In addition, the single lens reflex type electronic still camera 101, whose casing 102 forms a rough L shape in the plan view that is asymmetrical in the left/right direction relative to the plane M that includes the lens optical axis and the viewfinder optical axis, poses problems in that its weight balance is different from that of a typical silver halide type single lens reflex camera in the prior art and that the left side of the casing 102 is awkward to hold by hand, resulting in a great reduction in operability and ergonomics.
Furthermore, since the image-capturing element 105 is provided at a position close to the first electric circuit board 108, the second electric circuit board 109 and the illuminating light source 110, the temperature at the image-capturing element 105 is caused to rise by the heat generated at the first electric circuit board 108 and the second electric circuit board 109 and the heat generated by the illuminating light source 110 to lead to a poor S/N ratio at the image-capturing element 105, which, in turn, results in deterioration in the image quality. It is to be noted that while it is conceivable to separate the image-capturing element 105 over a distance from the first electric circuit board 108 in the front/rear direction to prevent the temperature at the image-capturing element 105 from rising, this configuration will increase the entire thickness of the casing 102. Therefore, this solution is not desirable from the viewpoint of improving the operability.
An object of the present invention is to provide an electronic still camera which achieves miniaturization through a reduction in the entire thickness of the casing, achieves operability substantially equal to that of a silver halide type single lens reflex camera in the prior art with a similar shape thereto and prevents the image quality from becoming poor by ensuring that the image-capturing element is not affected by the heat generated at electric circuit boards.
In order to attain the above object, an electronic still camera according to the present invention has a casing in which an image-capturing element is provided. And the casing comprises: a body middle portion in which the image-capturing element is provided in close proximity to a rear wall of the body middle portion; a grip unit that is formed continuous to the body middle portion on one side in a left/right direction and projects out further forward relative to a front wall of the body middle portion; and an electrical part housing unit that is formed continuous to the body middle portion on another side in the left/right direction and has a housing space. One or more recording compression circuit parts are provided inside the grip unit; and one or more image display parts are provided inside the electrical part housing unit.
Another electronic still camera has a casing in which an image-capturing element is provided. And the casing comprises: a body middle portion in which the image-capturing element is provided in close proximity to a rear wall of the body middle portion; a first electrical part housing unit that is formed continuous to the body middle portion on one side in a left/right direction and has a housing space; and a second electrical part housing unit that is formed continuous to the body middle portion on another side in the left/right direction and has a housing space. One or more high heat generating electric circuit boards are provided inside the first electrical part housing unit; and one or more high heat generating electric circuit boards are provided inside the second electrical part housing unit.